Sonia Baban, MD
Bjarte Sørensen, BSc(Med) MB BS, Specialist in general practice (Norway), FRACGP
Hjelmeland General Practice Surgery
Introduction
The aorta lends itself to sonography through its position and composition. Population
screening for abdominal aortic aneurysms (AAA) by general practitioners (GPs) has
been shown to be feasible [1]
[2]
[3]
[4]. Also on clinical indication, point-of-care ultrasound (PoCUS) may be an accurate
diagnostic tool for aortic pathology in the hands of generalists such as GPs [5] and emergency physicians [6] in the unselected population.
Case report
We present a case of the discovery of an aortic dissection in a 71-year-old female
in our GP clinic in rural southwest Norway. She has a history of hypertension and
polycythemia rubra vera. She experienced symptoms of chest pains radiating to the
neck and upper extremities the evening before. She sought help with the emergency
services that evening, but the pains subsided, an ECG was taken and was concluded
to be a normal reading. The pain returned and she was unable to sleep due to intense
pains in which the patient felt the sudden need to abduct her upper limbs. Additionally,
she experienced paresthaesia in her left arm and intermittent left sided chest pain,
along with abdominal and back pain.
The pain kept changing character and she presented with mild to moderate pain in her
lower right quadrant that radiated towards her upper right quadrant the next morning,
with no dyspnoea or chest pains.
On examination, her inter-arm blood pressure measured a difference of 7 mmHg (left
arm 162/109 and right arm 155/98) and she had a pulse of 102. There was general, mild
tenderness upon palpation of her abdomen. Her ECG showed a new case of right bundle
branch block.
The history and findings suggested an increased pre-test probability for aortic pathology.
The patient’s abdominal aorta was examined using a handheld portable ultrasound device
which showed a pulsating intraluminal structure in the abdominal aorta ([Fig. 1]). This was confirmed using the practice’s stationary ultrasound machine which showed
the same pulsating intraluminal structure throughout the whole length of the abdominal
aorta, thereby excluding the possibility of an artefact. At this point the patient
mentioned that her father died due to an aortic dissection at the age of 70.
Fig. 1 Transverse aorta (Ao) mid-abdomen showing intimal flap. IVC = Inferior vena cava.
The proximal end of the abdominal aorta measured 3.8 cm in diameter compared to 2.2 cm
in diameter proximal to the point of bifurcation. A radiologist was consulted by video
and the findings of an aortic dissection was concluded.
The patient was air lifted to the hospital where a CT of the aorta confirmed a Stanford
type A (De Bakey type I) aortic dissection. She was immediately transferred to the
nearest appropriate centre for surgical treatment.
Discussion
Although the annual incidence of aortic dissection is as low 2–15 per 100 000 [7], and indeed, this being the first case presenting to our rural practice the last
decade or so, we were able to accurately diagnose it using ultrasound. The pathognomic
pulsating intimal flap was immediately obvious to both authors and is an example of
how general practice works in general – having a broad experience in normality and
thus a high sensitivity for detecting the abnormal.
The dangers of using PoCUS by generalists in an unselected population with low disease
prevalence are of course both over- and under-diagnosis. However, with the right level
of pre-test probability gained through history taking and examination, research has
shown that PoCUS may be a valuable tool in the generalist’s hands for a large variety
of indications [8]. In our case, we had enough information to admit the patient to hospital regardless
of the ultrasound findings, but they provided reason for immediate large bore vascular
access, a much more pointed referral and the choice of a more rapid mode of transfer
through helicopter retrieval which would not have been indicated without the diagnosis.
The patient has consented to the case presentation. The authors have no conflict of
interests.
Video Transverse scanning of the abdominal aorta using a handheld ultrasound device, starting
just proximal for the bifurcation and moving proximally towards the epigastric area,
interrupted by bowel gas artefacts.
